Adjustable chair seat



CII. 8, 1946. T ELLEMAN ErAL 2,409,114

ADJUSTABLE. CHAIR SEATl Filed May 18. 1944 2 Sheets-Sheet l Iil Ti, zz

Oct. 8, 1946. T..ELLEMAN ETAL ADJUSTABLE CHAIR SEAT Filed May 18, 1944 2Sheets-Sheet 2 lil INVENTOR. TOM Zawya/V Y BY 20;/ W Jam/50M Afro/ENE?.

Patented ct. 8, 1946 STATES PATENT OFFICE ADJUSTABLE CHAIR SEATApplication May 18, 1944, Serial No. 536,092

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This invention relates to an improvement in adjustable chair seatsupports of the lockable, laterally-movable and revolving type.

An object of the invention is to provide a revolving andlaterally-movable chair seat support which will automatically lockagainst rotation when revolved to the front position and willautomatically unlock for free rotation only when the support is movedlaterally to its fully retracted position.

A further object is to provide a laterally-movable seat support whichwill freely slide under body thrust of the occupant and not increasebearing pressures between relatively sliding parts as the seat supportis moved laterally to its fully extended position.

The foregoing objects are accomplished by providing a locking leverCarried by the rotatable slide support or guide box and engageable withthe flange of the relatively-xed spindle-carrying bearing to preventrelative rotation therebetween. The locking lever is spring-biased toengage with a notch in the relatively-fixed spindle bearing uponregistration therewith. The locking lever is also provided with acamming surface which is engaged by the chair seat roller frame slidewhenever such slide is moved to its fully retracted position. Suchengagement will move the locking lever against the compressive force ofits biasing spring to a position where it cannot enter the notch eventhough in registration therewith.

To provide for free lateral movement of the chair seat roller frameslide, the slide is provided with spaced non-metallic rollers carried ini'lxed relationship to each other by stud shafts secured to the slide.These rollers t in tracks having upper and lower flanges provided on theslide support or guide box. The support is carried by a spindle which isrotatively mounted in the relatively-xed bearing. Because the rollersare carried by the slide and are therefore always the same distanceapart, the effective lever arm through which weight on the slide acts onone roller as a fulcrum with respect to the other roller does notincrease as the slide is moved from its fully retracted position to itsfully extended position. Thus bearing pressures do not increase as theslide is extended.

The novel features, which are considered characteristic of theinvention, are set forth wtih particularity in the appended claims. Theinvention itself, however, both as to its organization and its method ofoperation, together with additional objects and advantages thereof, willbest be understood from the following description of a spe- 2 cieembodiment when read in connection with the accompanying drawings, inwhich:

- Figure 1 is a top plan view of an adjustable chair seat supportembodying the present invention, a part being broken away for the sakeof clarity;

Figure 2 is a view partly in side elevation and partly in verticalcross-section taken on the line 2-2 of Figure 1, the chair seat beingshown in full with a. section broken away therefrom for the sake ofillustration, with the roller frame slide in its fully extendedposition;

Figure 3 is a View partly in side elevation and partly in verticalcross-section similar to the View of Figure 2 showing the roller frameslide in its fully retracted position; and

Figure 4 is a View in cross section taken on the line 4-4 of Figure 1.

Referring in greater detail to the drawings, the chair seat supportcomprises a base of well-known design (not shown) by which the column IBis xedly supported to the floor, deck or other supporting surface. Thecolumn II] carries at its upper end a spindle-carrying bearing or hubII. The hub I I has a lower portion provided with radial fins orstrengthening'ribs by which it is securely held Within the column I. Theupper end of the hub II is provided with a large cylindricalshapedhollow cap I2. The edge of this cap is provided with a notch I3 which isadapted to receive and engage the dog of a locking lever for the purposeof preventing rotation of the chair support as will be hereinafterdescribed. The upper surface ofthe cap has integrally positioned thereona projecting pin lil which acts as a centering post for a biasingspring. The upper surface is also provided with twodiametrically-opposed abutments I5 to limit the rotational movement ofthe seat support relative to the cap. The spindle-carrying bearing II,as is wellknown in the art, has a longitudinal bore for receiving androtatively supporting a spindle- An upwardly projecting circular ange I6encircles the perimeter of the top of this bore. The ange it forms asupport and centering piece for the coiled biasing spring, as will behereinafter more fully described. I'he hub II is preferably'made of castiron in order to obtain proper wearing qualities.

A vertically-positioned spindle I1 has its lower portion rotativelycarried in the bore of the hub II. The bottom end of the spindle isprovided with a chamber, and it rests against the bottom of the bore inthe hub II to carry the vertical load. The spindle may be provided withan annular groove I8 into'which the end of a set'screw 3 I9 is fitted,permitting the spindle to have rotative movement relative to the hub Ilwhile preventing it from being withdrawn.

To the upper end of the spindle, there is lixedly positioned a slidesupport or guide box designated generally at 29. The guide box 2.0comprises a top yplate 2l and 4a lower plate 22. These plates are ixedlyheld in parallel spaced relationship by a pair of parallel side plates23.

The side plates 23 are spaced inwardlyfrom the opposite sides of the topand bottom plates 2l and 22. rIhe plates 23 are substantiallyico-extensive with the top and bottom plates 2i. The top and bottomedges of the side plates 23 may be provided with projecting lugs 24which extend through suitable aligned openings in the top and bottomplates 2l and 22 and are'then riveted or swaged to securely hold theplates in fixed posi.- tion. The portions of the top and bottom plates2l and 22 .extending from the outer faces ofthe side plates 23 to theedges thereofform the upper and lower bearing lsurfaces of a track forrollers. The outer face of the plates 29 also forms a lateral guide forthe rollers on such track. The lower plate 22 may have the margin of itsside edges turned upwardly as at 25 for the purposes of appearance andthe retention of lubricant. The guide box 29 is xedly secured to thespindle ll to prevent relative rotative movement therebetween. Toaccomplish this, the upper end of the spindle I1 is provided with areduced portion which has a press fit in a suitable aperture provided inthe lower plate 22. A hollow cylindrical spacer 26 is positioned betweenthe upper and lower plates 2| and 22 and loosely surrounds the reducedupper portion of the spindle I1. A further reduced portion on thespindle l1 is forced through a hexagonal holo provided in the top plate2|. In the assembly the upper reduced portion on the spindle l1 isriveted or mushroomed outwardly Yso as to ll .the intricacies of thehexagonal opening to prevent the spindle from turning relative to theguide box. It will be seen thatwith this construction,

the shoulders resulting from forming the two Vreduced portions on thespindle engage the under .surfaces of both the top and bottom plate toequalize stress thereon. The addition of the spacer 29 also equalizesand distributes `pressure t on both top and bottom plates.

The guide box 20 with its spindle l1 inserted in the bearing Il hasrelative rotative movement with respect thereto. It is desirable,however,

to bias the guide box 29, and hence the Seat which it carries, to apre-determined forward position. To accomplish this, a biasing or returnspring 21 is coiled about the flange IB with each of its ends projectingradially on opposite sides of the projecting pin i4. When Isopositioned, the spring is under a slight tension. 1t is preferable touse about 3 coils of spring to give a sufficient amount of movementVwithout unduly tensioning the spring. A lug 28 is riveted to the lowerplate 22 and projects downwardly therefrom and in between theradially-extending ends of spring 21. As the guide box 29 is rotatedrelative to the bearing Il in either direction, the projection 28 willmove one or the other of the radial projecting ends of spring 21, whilethe other such end is held against rotation by the projecting pin lll.Thus tension is applied on the spring 21. As soon as turning force isremoved from the guide box 29, the spring 21 will move it back to theoriginal forward set-up position. In this forward set-up position, thepin I4 and lug 28 are in alignment. The guide box and the spring have afull travel of over 90 to each side of the forward set-up position.Further movement is ar rested by the action of the abutments l5 which 5engage the radially extending end of the spring 21 to prevent furthermovement.

It is desirable to lock the guide box 29 against rotative movement whenin the forward position, with the seat S extended, as hereinafterdescribed, as in this position the occupant of the seat will bebenefited by lack of movement. This is particularly true where the seatis being used on board vessels, club cars, or other places where themovement of the floor or deck would cause the seat to rotate to theannoyance of the user .if it were not locked. To accomplish locking ofthe seat in this position, the guide box carries a locking lever orpivot latch 29. The latch 29 is pivotally held by a bracket 30 whichcomprises two members positioned on opposite sides of the locking lever29 and extending between the top plate 2| and lower plate 22 to whichthey are suitably secured. ,A pivot pin 3l extends between these sidemembers and through an appropriate aperture in the locking lever 29 toform the pivotal connection. The right-hand end of the locking lever 29(as viewed in Figures l, 2 and 3) has an upper cam surface 32. 'I'hiscamming surface in the normal position of the locking lever 29 extendsthrough a slot 33a in the top plate 2l. Below the cam surface 32 thelocking lever 29 is provided with a downward projecting Ispringcentering lug. A coil compression spring 33 is held in place by this lugand presses against the lower plate 22 where it is held in place by asimilar spring centering lug fastened to the lower plate 22. Thus thelocking lever 29 is urged .in counter-clockwise direction, as viewed inFigures 2 and 3. The left-hand end of locking lever 29 is provided witha-do'wnwardly-projecting dog 34. The dog @il extends through a slot 35provided in the lower plate 22 and fits within the notch i3 formed inthe cap l2 whenever the two are in register. As the notch 'I3 isopposite from the projecting pin l, it is apparent that the dog 34 willautomatically enter the notch i3 whenever the guide box -is in theforward position. The locking member 29 is vlaterally oiset, as shown inFigure l, to clear the spindle 11. Hence, the bracket '3G vis not on thecenter line of the device but to one side thereof. However, the dogr 34is substantially on the centerline ofthe guide box. To guide theleft-hand end of locking lever 29 and to cause the dog 3A to always ridein the slot A35, there is provided an inverted 'Ll-shaped bracket 36.The bracket '39 has its legs stradclling the locking lever 29 and the'lower portions thereof out-turned and riveted or otherwise suitablysecured to the lower plate 22.

The guide box 29 slidably carries a chair seat roller frame slideassembly, designated generally at 31. The roller frame 'lcornprises vatop member 3B which has downwardly-depending 'opposite sides 39. Thesides 39 straddle 4the'edges of upper plate 2l and extend almost totheedges of the turned-up portions 25 of "lower plate 22. The length of theroller frame 31 is approximately 1/2 the length of the guide box 29. Theside arms or spiders 40 may be o'f any designated shape and sizeapplicable to the size of the seat desired and are nested in overlapping:position on the roller frame 31 and secured by having their side legsriveted lto the depending sides 39 as `indicated at 4I. Each side arm 39.has a pair of headless stud shafts 42 which extend inwardly toward andterminate just short of the side plates 23, when the roller frame 3'! isin its normal position. The stub shafts 42are provided with anintermediate flange 44 (as shown more clearly in the broken away sectionof Figure 1) which backs up against the inner surface of sides -33 tohold the stubs in place when their ends are riveted against the outersurfaces of sides 4i). Each shaft 42 is positioned adjacent the yendofthe sides 39 to provide the maximum distance between them. Rollers 43are positioned on the'stub shafts 42 before the roller frame 3! isassembled to the guide box 20. The diameter of these rollers 43 is suchthat they roll'on one and have close sliding t with the other of eitherthe top or lower plates 2| and 22 forming the roller track. This permitsthe rollers 43 to move easily in the tracks but prevents any up anddownmovement. The rollers 43 are provided with hubs which have a slidingfit on the outer surface of the side plates 23 and rotating fit on theflanges'44 of studs 42. Thus the rollers 43 act as spacing members forthe guide box and roller frame 3'! to prevent lateral movementtherebetween, 'as well as vertical movement. The rollers 43 arevpreferably madeof non-metallic material such as plastics which have alow coefcient of friction, thus reducing wear and noise and renderingfree movement.

The top plate 2l at its left-hand end (as viewed inFigures l, 2 and 3)is provided with an abutment 45 which is turned up after the rollerframe and rollers are assembled on the guide box 20. The abutment 45engages with the forward edge of the top plate 38 to limit the movementof the roller frame 3! and determine its fully extended position, asshown in Figures 1 and 2. The righthand end of the top plate 2l of theguide box is likewise provided with an abutment 4E which is turned upafter the roller frame 3'! is assembled in position. The abutment 4Sengages with the right-hand end of top plate 38 to limit the movement ofthe roller frame 3'! to the right, as is shown in Figure 3. Thisdetermines the fully retracted position of the roller frame.

With the roller frame constructed as shown, the distance between therollers remains the same whether the frame is in its fully extended orfully retracted position, or at any intermediate position. This isimportant in that when any weight is placed on the seat S the effectivelever arm, through which this weight acts on one roller as a fulcrum andon the other roller as an abutment, does not change as the roller frameand seat are slid from one to the other of these eX- treme positions.This prevents the occurrence of a binding action as the seat is slidoutwardly to its extended position.

Whenever the seat is in the fully retracted position, as show n inFigure 3, the right-hand marginal end of top plate 38 of the rollerframe engages the camming surface 32 of the locking lever 29 and causesthat lever to move clockwise to the position shown in Figure 3, with thedepending dog 3Q out of engagement with the notch i3 in the cap l2. Thuswhenever the seat S is slid to its fully retracted position, it may berotated relative to the hub H a maximum of 90 on either side of itsforward position. This permits the prospective occupant to easily placehimself on the seat S. The influence of the biasing spring 2l, however,will tend to return the seat S to the forward position, and as soon asit is slid a short distance from its fully retracted position, the dog34 will be released to again engage the notch I3. l

It is desirable to maintain the seat in its fully extended position, asshown in Figure 2. To obtain this result, a latching lever 4'! iscarried on the roller frame 3! in such a way as to be automaticallyengageable with the forward edge of the top plate 2| whenever the seatis moved to the fully extended position. The latching lever 41 hasadownwardly-depending finger `liwhich rideszon the top of top plate 2l(see Figure 3).. except when the roller frame is moved toits fullyextended position. At this time a compression spring 49 urges the lever`4'! downwardly so that the finger 43 will drop into the position shownin Figures 2 and 4 'to engage the edge Voftop plate 2i. Thespring 49acts between a washer 50 carried on the end of a through rod 3| and thelever 4l. The rod 5i extends through an openingin the lever :il and? isfastenedto'the top plate 38 of the roller frame 3'! in any suitablemanner. Apair of rivets 52 loosely hold the lever 4'! t0 the top plate38 so that it may rock.'v itself and then relative to theplatesuiciently to lgive it the movement necessary to have'. the..latchengage and disengage with the edge of top plate 2l. The lever arm 4'! ismade long enough to extend substantially to the side of the seat S whereit may be :easily engagedby the hand of the occupant of the seat toraise it from its latching engagement whenever it is desired to slidethe seat S to its retracted position. v

From the foregoing it is seen that'whenever the seat is revolved to aforward position, the dog 34 will automatically engage with the notch i3to prevent rotation unless the seat is at that time withdrawn to thefully retracted position shown in Figure 3. When the seat is fullyretracted, it may be swung to either side' of its forward position.However, the occupant need not operate any latch to lock the seat in theforward position, as it will automatically lock in thisposition as itrevolves to the front position and slides forwardly to extendedposition. The only control which the operator needs to 'manipulate isthe latching lever 4l. When the seat is in its fully extended positionin order to slide it to its fully retracted position, it is necessaryfor the occupant to place his fingers under the edge of the seat S andraise the end of latch 4'! upwardly to release the nger 48 fromengagement with the front wall of the top plate 2i. After this has beendone, the seat may be slid back far enough to disengage the dog 34 andthe seat swung to either side of forward position.

Although there is shown and described specic embodiments of theinvention, many modifications thereof are possible. The invention is notto be restricted except insofar as is necessitated by the prior art andby the spirit of the appended claims, which are: i

1. In a chair seat support, a relatively-fixed bearing, a slide supportmounted for rotation with respect to said bearing, a locking levercarried by one of said relatively movable parts and engageable with theother to prevent relative movement therebetween, a seat-carrying slidecarried by said slide support and laterally movable with respectthereto, and camming means between said locking lever and Said slide tomove said locking lever to disengaged position when said slide is in itsfully retracted position.

2. In a chair seat support, a relatively-fixed .Y

bearing provided with an outwardly extending ange having a notchtherein, a slide support rotatively mounted in the said bearing, alocking lever carried by said slide support and spring biased to engagewith said notch to prevent relative rotative movement between said slidesupport and said relatively-fixed bearing, a seat-car.- rying slidecarried by said slide support and laterally movable with respectthereto, and. camming means acting between said locking lever and saidslide and operable when said slide is in its fully retracted positionrelative to said fixed bearing to move said locking lever against itsspring bias to prevent engagement with said notch.

3. In a, chair seat support, a relatively-fixed bearing, a slide supportmounted for rotation with respect to said bearing, a locking levercarried by one of said relatively movable parts and engageable with theother to prevent relative movement therebetween, a seat-carrying slidecarried by said slide support and laterally movable with respectthereto, camming means between said locking lever and said slide to movesaid locking lever to disengaged position when said slide is in itsfully retracted position, and a spring biased latch operable to holdsaid slide in its fully extended position relative to said slidesupport.

4. In a chair seat support, a relatively-fixed bearing, a slide supportmounted for rotation with respect to said bearing, a locking levercarried by one of said relatively movable parts and engageable with theother to prevent relative movement therebetween, a seat-carrying'slidecarried by said slide support and laterally movable with respectthereto, camming means between said locking lever and said slide to movesaid locking lever to disengaged position when said slide is in itsfully retracted position, and a spring biased latch carried by saidslide and engageable with the edge of said support to hold said slide inits fully extended position relative to said slide support.

5. In a chair seat support, a relatively-fixed bearing member providedwith an outwardly extending fiange having a notch therein, a slidesupport mounted for rotation with respect to said bearing and comprisinga top plate and a lower plate spaced apart by side plates extendingtherebetween, said side plates being spaced inwardly from the edges ofsaid top and lower plates to form a pair of tracks, a locking leverpivotally mounted between said top and lower plates, said plates eachhaving a slot therein, said locking lever having on one end a dogextending through one of said slots and engageable with said notch, andon the other end a camming surface extending through the other of saidslots. spring means urging said locking lever in a direction which willcause said dog to enter said notch when in registration therewith, achair seat carryingv slide having a top portion and down-turned sideflanges, said down-turned side flanges overlapping the edges of said topplate, a plurality of stud shafts extending inwardly from said sideflanges, non-metallic rollers rotatively mounted on said shafts andriding in said tracks, one side of said rollers slidably bearing againstthe outer surfaces of said side plates to guide said slide relative tosaid support, said slide in its fully retracted position beingengageable with said camming surface to move and maintain said dog outof engagement with said notch, and a latching lever carried by saidslide and engageable with said support to maintain said slide in fullyextended position.

6. In a chair seat support, a slide support comprising a top plate and alower plate spaced apart by side plates extending therebetween, saidside plates being spaced inwardly from the edges of said top and lowerplates to form a pair of tracks, a chair seat carrying slide having atop portion and down-turned side anges, said downturned side flangesoverlapping the edges of the top plate of said slide support,non-metallic rollers carried on the inner surface of each of saiddown-turned side ilanges, said rollers riding in said tracks and beingxedly spaced relative to each other and to said slide top portion.

TOM ELLEMAN.

ROY W. JOHNSON.

